Understanding the influence of minerals and amino acids on the saltiness perception from samphire extract

Abstract

Halophytic species like Salicornia provide an intense salty taste which is unexplained by their sodium content alone. The objective of this study was to determine the composition of samphire extracts and relate this to the sensory profile of samphire fortified food product. Fresh samphire was freeze-dried and analysed for mineral and amino-acid content. Samphire extract was also added into a nachos base at 2.5% and 3.4% (w/w), while nachos with 0.7% and 1.0% salt (NaCl) were used as controls to be equivalent in sodium content. Sensory profiling was carried out by a trained sensory panel (n = 14) where a consensus vocabulary was developed, followed by samples being scored individually, in duplicate, using unstructured line scales.Samphire extracts were found to contain minerals, including Na (12–14 g/100 g), K (1–1.5 g/100 g) and Mg (0.3–0.5 g/100 g). Free amino acids, including lysine, glutamic-acid, aspartic-acid, arginine known to influence salty taste, were also present. The sensory results concluded that 2.5% addition of samphire extract significantly increased salty taste compared to the control product at the equivalent sodium level (0.7% NaCl) and reached comparable salty taste to the 1% salt control. Umami taste and green vegetable flavour were also significantly higher with samphire samples vs salt controls. In conclusion, the minerals and amino acids may collectively contribute to the salty taste of samphire extract, indicating that samphire can be used to achieve sodium reduction in snack products; however, the green vegetable flavour warrants further investigation as it may be inappropriate in some food products.